[PATCH] scripts: improve checkstack

[Stephen Hemminger <shemminger@vyatta.com>]

Turn on strict checking, and get rid of annoying use of prototype.
Fix syntax error in declaration

Use efficient sort algorithm by using schwartzian transform.
  http://en.wikipedia.org/wiki/Schwartzian_transform

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>

--- a/scripts/checkstack.pl	2010-02-19 21:57:57.609178016 -0800
+++ b/scripts/checkstack.pl	2010-02-19 22:23:16.038241212 -0800
@@ -21,6 +21,8 @@
 #
 #	TODO :	Port to all architectures (one regex per arch)
 
+use strict;
+
 # check for arch
 #
 # $re is used for two matches:
@@ -104,19 +106,11 @@ my (@stack, $re, $dre, $x, $xs);
 	}
 }
 
-sub bysize($) {
-	my ($asize, $bsize);
-	($asize = $a) =~ s/.*:	*(.*)$/$1/;
-	($bsize = $b) =~ s/.*:	*(.*)$/$1/;
-	$bsize <=> $asize
-}
-
 #
 # main()
 #
 my $funcre = qr/^$x* <(.*)>:$/;
-my $func;
-my $file, $lastslash;
+my ($func, $file, $lastslash);
 
 while (my $line = <STDIN>) {
 	if ($line =~ m/$funcre/) {
@@ -173,4 +167,7 @@ while (my $line = <STDIN>) {
 	}
 }
 
-print sort bysize @stack;
+# Use Schwartzian transform to sort by last field (size)
+print map { $_->[0] }
+      sort { $b->[1] <=> $a->[1] }
+      map { [$_, /:\t*(\d+)$/] } @stack;